Device for lowering and raising a movable structure from or to its support



1962 E. R. PERRY ETAL 3,021,410

DEVICE FOR LOWERING AND RAISING A MOVABLE STRUCTURE FROM OR TO ms SUPPORT Filed April 30, 1957 2 Sheets-Sheet 1 17 ff Zj [6 29' f5 Z Z] Z? 46 a 1 I r 4 I I 1/7 I t /3 Z 0" 111 1 7 if 1 3 4 .2

g- JMMM' flgpdt @f. 51W 9W 1. u R

A VW m2 1962 E. R. PERRY ETAL DEVICE FOR LOWERING AND RAISING A MOVABLE STRUCTURE FROM OR TO ITS SUPPORT 2 Sheets$heet 2 Filed April 50, 1957 United States Patent 01 DEVICE FOR LOWERING AND RAISING A MOV- ABLE STRUCTURE FROM OR TO ITS SUPPORT Elijah R. Perry, Dallas, Tex., and Henry, L. Peek, Wellesley, Mass., assignors to Allis Chalmers Manufacturing Company, Milwaukee, Wis.

Filed Apr. 30, 1957, Ser. No. 656,149 9 Claims. (Cl. 200-150) This invention relates to electrical switchgear and more particularly to apparatus for lowering and elevating the oil containing tanks of oil circuit breakers.

Inspection of oil circuit breakers of conventional design is frequently accomplished by dropping the oil tank, which tank is generally movably mounted with respect to the relatively fixed cover structure of the breaker,

lifters a great deal of time and manual labor are needed to operate these devices.

Therefore, in accordance with the invention claimed 7 a new and improved device is provided for raising and lowering tanks of circuit breakers supported above or below a predetermined level comprising in combination a fluid motor having relatively movable cylinder and piston elements. The cylinder element is provided with a fluid inlet and outlet port. Means are provided for connecting one of the cylinder and piston elements to a supporting structure and for supporting the tank of the circuit breaker by the other of these elements. A source of fluid under pressure employing reservoir means is connected tothe inlet, outlet port and is controlled by a valve means which causes fluid under pressure to flow from the source to the cylinder element to cause relative movement of the cylinder and piston elements and for draining fluid under pressure from the cylinder element to the reservoir means.

It is, therefore, one object of the present invention to provide a new and improved tank lowering and lifting apparatus.

Another object of this invention is to provide a new and improved tank lowering and lifting apparatus which is adaptable to most oil circuit breakers by simply removing a part of the frame securing means, such as fastening bolts, which normally support the tank in depending relation to the cover structure.

A further object of this invention is 'to provide a new and improved tank lowering and lifting device having cooperative means between the device and the circuit breaker supporting framework which enables the device to be detachably secured to the framework so that reaction forces created by the moving tank do not disturb th devices lifting or lowering operation.

A still further object of this invention is to provide a new and improved tank lifter which is adapted to raise or lower tanks of different sizes within a practical range.

A still further object of this invention is to provide a new and improved self-contained fluid actuated portable tankmover which can be readily movedfrorn framework to framework thereby enabling a single tank mover to ac-I commodate a plurality of pole units.

Objects and advantagespther than those set forth will be apparent from the following description when read in connection with the accompanying drawings,,in whichz FIG. 1 is a diagrammatic front view, on a reduced scale, of a plurality of pole units of an oil circuit breaker mounted on a supporting framework showing one embodiment of the tank mover in operative position for lowering or raising the oil tank of one pole unit and embodying the invention; 7

FIG. 2 is a plan view of the structure shown in FIG. 1;

FIG. 3 is an enlarged partial cross sectional view of FIG. 2 taken along the line -III--III showing one of the tank movers in elevated position;

FIG. 4 is an enlarged partial cross sectional view of the structure shown in FIG. 3 with the tank mover in its lowered position; I

FIG. 5 is an enlarged partial cross sectional view of FIG. 2 taken along the line VV showing the means for detachably mounting the tank to the supporting structure;

FIG. 6 is a diagrammatic view of the pneumohydraulic system used with the tank lifting and lowering mechanism and embodying the invention;

FIG. 7 is a diagrammatic front view, on a reduced scale, of a modification of the tank lifting and lowering structure shown in FIG. 1 and embodying the invention;

FIG. 8 is a plan view of the structure shown in FIG. 7;

FIG. 9 is an enlarged front view partly in section of the portable pneumohydraulic actuating means'shown in FIGS. '7 and 8;

. FIG. 10 is a plan view of the structure shown in FIG. 9; and

FIG. 11 is an end view partly in section of the structure shown in FIG. 9.

Referring more particularly to the drawing by characters of reference FIG. 1 illustrates a framework 15 supporting a plurality of pole units 16 of a. polyphase oil circuit breaker 17. Each unit shown comprises a relatively fixed domelike cover structure 18 and an oil containing tank 19 detachably secured to cover structure 18 around a peripheral portion thereof and depending therefrom. The cover structure 18 which is suitably mounted on framework 15 supports the breaker contact structure (not shown) which includes for each phase a stationary contact and a coacting movable contact. The stationary contacts are connected to the lower ends of the leadin bushings 20 which extend through the top of the cover structure 18. The pole unit contacts arecontrolled by means of a tripping mechanism in g a control box 21 mounted on framework 15 by means of a plurality of rods and toggle mechanisms (not shown) connected to pull rod levers passing through housing 21' for operating the movable contact or contacts of the pole units in a customary manner.

The framework 15 provides a rigid and substantial support for the pole units, and is of a height to give easy access to the circuit interrupting elements for adjustment or service when the tanks are lowered. The tanks '19 are normally held in their upper position by a plurality of detachable securing means such as, for example, fastening bolts 22 extending through aligned apertures in lugs 23. and 24 which are secured to the cover structure 18 and tanks 19, respectively. In the present instance four fastening bolts equally spaced in peripheral positions around the cover are employed for supporting each of the tanks in depending relation to the cover structure although any number of bolts and lugs may be used if so desired. FIG. 5 illustrates a bolt 22 in fastening relation with lugs 23 and 24 of cover structure 18 and tank 19, respectively. 'When a tank is to be lowered from the position shown in FIG. 1, two of the diametrically positioned bolts are unfastened and removed and the tank lifting and lower the tank lowering and lifting mechanism comprises a pair of readily applied single directional acting hydraulically operated fluid motors 26 each comprising cylinder, piston and piston rod elements 27, 23 and 29, respectively, which quickly lower and raise the tanks of the frame mounted breakers without the necessity of manual effort. Motors 26 may be actuated by energy stored in pneumohydraulic accumulators or may be provided as needed by hand or motor operated pumps. if the breakers are controlled by a pneumohydraulically operated control mechanism of the type now used in the trade the source of fluid under pressure for the tank lowering and raising mechanism may be from this mechanism. FIGS. 1 and 2 illustrate a breaker utilizing this type of mechanism in box 21.

The essential elements of such a pneumohydraulic power unit as shown in the schematic diagram of FIG. 6 may comprise a reservoir 30, a hydraulic power pump 31 and/ or hand pump 32, a check valve 33 which may be built into either one of the pumps and two hand operated valves 34 and 35 connected together in the pipe system shown for connection to the fluid motors 26. Quick coupling connections 36 connect the pipe system through a flexible hose 37 to motors 26. An accumulator 33 may be provided as shown in FIG. but is not necessary. If the accumulator is used suitable orifices must be provided to control the rapid rise of fluid pressure in the pipe system to control the speed of movement of tanks 19. The power unit may be of the type used as standard equipment on pneumohydraulically operated breakers of the type shown in United States Patents 2,730,589 and 2,765,378 or may be of a separate, portable type as shown in FIGS. 7l1 of the drawings. The portable type of power unit is easily moved from breaker to breaker. The power pump 31 may be operated from any available alternating or direct current source, or a power unit complete with battery operated motor and battery may be supplied thus eliminating the need for commercial electrical energy and the need for a separate hand pump for use when the power source fails.

The flexible hose assembly 37 comprises one long hose section 39 for connection to the power unit, two shorter hose sections 40 and 41 coupled to the longer hose section 39 by means of a T 42 and three female halves of quick couplings 36 for connecting the hose 37 to the power unit and parallelly operated motors 26. The male half of each coupling is provided with a dust tight cap. Each half of the coupling employs a valve which quickly closes the coupling to prevent any loss of oil. The two short hose sections 40 and 41 are of such short length that they do not dangle underneath the tank. Thus the tank does not pinch or cut the hose when it reaches floor level.

The cylinder element 27 of each motor 26 is provided with a port 45 to which the hose sections 40 and 41 are connected andwhich is used as an outlet port during a tank lowering operation and as an inlet port during a tank raising operation. The piston rod or ram 29 of motors 26 are each provided at their upper end with a nut which has a lower conical face 46 for properly centering it in a bolt hole 47 of lug 23 mounted on the cover structure 18 or framework 15. The top ends of cylinder element 27 are likewise each provided with a conical surface 4 8 which is used to properly center it in lug 24 mounted on the tank of the circuit breaker structure. The piston rod 29 is screwed into a blind hole in piston 26 thereby eliminating the need for a seal at the lower end of the rod. Suitabie piston rings 51 are used around the periphery of piston 28 to provide a substantially fluid tight seal. The space below piston 28 is equipped with a dust filter 4-9 of felt or other suitable material to prevent the entrance of dirt as air passes in and out of vent holes $8.

The operation of the tank lowering and lifting mechanism is as follows:

The tank lowering and lifting mechanism is mounted on the breaker structure and connected as shown in FIGS.

1-6. FIG. 6 illustrates the desired piping connections. Assuming'that the entire'tank lowering and lifting mechanism has been filled with oil and that the breaker has been disconnected from the voltage supply, it is only necessary to remove two diagonally opposite tank bolts 22 from the breaker structure before the tank lowering and lifting device can be mounted on framework 15. As soon as the tank lowering and lifting device is mounted on framework 15 in the manner shown in FIGS. 3 and 4, that is by inserting the piston rod through the bolt holes in lugs 23 and 24, nuts 25 on the ends of rods 29 are tightened up thereby firmly securing motors 25 to framework 15. The remaining tank securing bolts 22 are then removed. The tank is then supported on top of the cylinder elements 27 of motors 25. Cylinder elements 27 are held the motor shortened position adjacent lugs 23 by the oil with which they are filled. The connection f hose 37 with the power unit has opened up all quick coupling valves so that when valve 35 shown in FIG. 6 is opened the weight of the circuit breaker tank filled with oil forces the oil from cylinder elements 27 through the flexible hose 3'7 and into reservoir 30 thereby lowering the tank to the floor. The size of the opening in valve 35 controls the speed with which the tank drops to the floor.

To raise the tank to the cover structure of the circuit breaker it is only necessary to close valve 35 and open valve 34. If the power unit of the tank lifter is equipped with a charged accumulator, oil under pressure from the accumulator will flow through hose 37 and into the cylinder elements 27 of motors 26 to force the cylinder elements upward thereby raising the tank to its cover structure. Speed control in raising the tank is usually obtained by use of suitable orifices in the base of the accumulator or in the pipe system to limit the speed of movement of the tanks thereby eliminating the possibility of opening valve 34 too wide causing a too rapid rise of the tank under direct action of the pneumatically charged accumulator. If no accumulator is used, no orifice is required. In this case valve 35 is closed, upper valve 34 is opened and pump motor 31 energized. A standard pump can lift the tank in approximately one minute.

If the tank lowering and lifting device is in its shortened position, that is with the piston rod within the cylinder element and the tank positioned on the ground, it is necessary to extend the piston rod manually fitting the end of the piston rod through the bolt hole of lug 23 and securing it thereto and then extending the tank lifter until the top of the cylinder element slips under the tank lifting lug 24. The tank lifting lug 24 has been slotted to permit inserting the ram from the side.

FIGS. 7-11 illustrate a portable tank lowering and lifting power unit mounted on a carriage 5h. The power unit comprises a motor driven pump 57 which has built into it a suitable reservoir of sufficient capacity to fill hose 37 and motors 26. Pump 57 is driven by an electric motor 52 which is energized by a battery 53. An on off switch 54 is provided for controlling the energizing and deenergizing of motor 52 for raising the tank to the cover structure in the manner described above under FIGS. 1-6. An exhaust valve 55 and control lever 56 therefor is provided for draining the fluid from cylinder elements 27 of motors 26 for lowering the circuit breaker tanks to ground or floor level.

In the drawings a pair of motors 26 is employed utilizing two cylinders so arranged that the points of attachment to the circuit breaker tank are sufiiciently above the center of gravity of the tank that any unbalance and resulting tipping of the tank will load up one or the other of the cylinder elements of motors 26 to restore the tank to a level position. The motor assemblies are so arranged that the piston rods point upwardly and provide means of attachment to the circuit breaker framework but remain stationary so that the cylinder elements provide the direct tank support and movement necessary to raise and lower the tanks. This arrangement eliminates metal parts of the tank lowering and lifting device from extending above the cover structure of the circuit breaker and into the high voltage area near the breaker bushings. Further the tank lowering and lifting motors are provided with only onefluid entrance and exit port and the same hose is used for draining fluid from motors 26 to lower the tank as is used for forcing fluid into motors 26 for raising the tanks to their cover structure.

As is readily noted from the specification and drawings only one pump and one set of controls are needed for operating both fluid motors 26 so that one operator can easily install, control and operate a tank lowering and lifting device. This newand improved tank movable unit can be quickly connected to and disconnected from a circuit breaker without theneed of any permanent pip ing, pulleys, levers, etc., mounted on the circuit breaker structure. I

The drawings illustrate the cylinder elements of fluid motors 26 as being movablewhile thepiston elements 28 are stationary, however, it is intended to be within the scope of this invention to provide a tank lowering and lifting device wherein the cylinder and piston elements are relatively movable. That is, either the cylinder-elements or the piston elements may be movable or both types of elements may be movable relative to eachother.

Although but a few embodiments of the present inven- T tion hve been illustrated and described it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. I I

What is claimed is:

l. A device for raising and lowering'a tank of a circuit breaker supported above ground or floor level by a frame structure comprising in combination a pair of single directional acting fluid motors arranged for parallel operation, said motors each comprising relatively movable cylinder and piston elements, said cylinder element of each of said motors being provided with a port, means for directly connecting one of said elements of each of said motors to said frame structure, means for supporting the tank of the circuit breaker by another of said elements of each of said motors, means comprising a source of fluid under pressure connected to said port of each of said cylinder elements of said motors, a reservoir connected said frame structure, means for supporting the tank of the circuit breaker by said cylinder element, means comprising a source of fluid under pressure connected to said port of said cylinder element, a reservoir connected to said port of said cylinder element, and valve means for draining fluid under pressure from said motor to saidreservoir for causing movement of said cylinder element relative to said piston element to lower the tank from the circuit breaker and for sequentially causing fluid under pressure to flow from said source to said cylinder element to cause movement of said cylinder element relative to said piston element to raise the tank to the circuit breaker structure.

4. A device for raising and lowering a tank of a circuit breaker supported above or below a predetermined level by a frame structure comprisingin combination a pair of single directional acting fluid motors arranged for parallel operation, said motors each comprising relatively movable cylinder, piston and piston 'rod elements, said cylinder element of each of said motors being provided with a port, means for directly connecting said piston rod element to said supporting structure, means for supporting the tank of the circuit breaker by said cylinder elements, means comprising a source of fluid under pressure connected -to said port of each cylinder element, a reservoir connected to said port of each of said cylinder elements, and valve means for draining fluidunder pressure from said motors to said reservoir for causingmovement of said cylinder elements relative to said piston elements to lower the tank from the circuit breaker and for sequentially causing fluid under pressure to flow from said source to said port of each of said cylinder elements of said I motors, and valve means for draining fluid under pressure from said cylinder elements to said reservoir for causing relative movement of said elements to lower the tank from the circuit breaker and for sequentially causing fluid under pressure to flow from said source to said cylinder elements to cause relative movement of said elements to raise the tank to the circuit breaker structure.

2. A device for raising and lowering a tank of a circuit breaker supported above or below floor level by a frame structure comprising in combination a fluid motor, said motor comprising relatively movable cylinder and piston elements, said cylinder element being provided with a port, means for directly connecting said piston element to said frame structure, means for supporting the tank of the circuit breaker by said cylinder element, means comprising a source of fluid under pressure connected to said port of said cylinder element, a reservoir connected to said port of said cylinder element, and valve means for draining fluid under pressure from said cylinder element to said reservoir for causing relative movement of said elements to lower the tank from the circuit breaker and for sequentially causing fluid under pressure to flow from said source to said cylinder element to cause relative to said cylinder elements to cause movement of said cylinder elements relative to said piston elements to raise the tank to the circuit breaker structure.

5. A device for raising and lowering tanks of a circuit breaker supported above or below a predetermined level under pressure to each of said cylinder elements, a reservoir connected to said port of each of said cylinder elements, and valve means for draining fluid under pressure from each of said cylinder elements through said port in each of said cylinder elements to said reservoir for causing movement ofsaid cylinder elements relative to said movement of said elements to raise the tank to the circuit piston elements to lower the tank from the circuit breaker and for sequentially causing fluid under pressure to flow from said accumulator through said port in each of said cylinder elements to cause movement of said cylinder elements relative to said piston elements to raise the tank to the circuit breaker structure. I

6. In combination with an oil circuit breaker including a relatively fixed cover structure, an oil containing tank, and a plurality of detachable securing'means for supporting said tank in depending relation to said cover structure at a plurality of peripheral positions, means for lowering and elevating said tank with respect to said cover structure comprising a fluid motor, said motor comprising relatively movable cylinder, piston and piston rod elements, said cylinder element being provided with a port, means for directly connecting said piston rod element to said cover structure after removal of and at the same peripheral position as at least one supporting means, means for supporting said tank by said cylinder element when said detachable supporting means are removed from the breaker, means comprising a source of fluid under pressure connected to said port of said cylinder element, a reservoir connected to said port of said cylinder element, and valve means for draining fluid under pressure from said motor to said reservoir for causing movement of said cylinder element relative to said piston element to lower said tank from said cover structure and for sequentially causing fluid under pressure to flow from said source to said motor to cause movement of said cylinder element relative to said piston element to raise said tank to said cover structure.

7. In combination with an oil circuit breaker including a relatively fixed cover structure, an oil containing tank, and a plurality of detachable securing means for supporting said tank in depending relation to said cover structure at a plurality of peripheral positions, means for lowering and elevating said tank with respect to said cover structure comprising a pair of single directional acting fluid motors, said motors each comprising relatively movable cylinder, piston and piston rod elements, said cylinder element of each of said motors being provided with a port, means for directly connecting said piston rod elements to said cover structure after removal of and at the same peripheral position of some of said detachable supporting means, means for supporting said tank by said cylinder elements when the remaining detachable supporting means are removed from the breaker, means comprising a source of fluid under pressure connected to said port of each of said cylinder elements, a reservoir connected to said port of each of said cylinder elements, and valve means for draining fluid under pressure from said motors to said reservoir for causing movement of said cylinder elements relative to said piston elements to lower said tank from said cover structure and for sequentially causing fluid under pressure to flow from said source to said motors to cause movement of said cylinder elements relative to said piston elements to raise said tank to said cover structure.

8. In combination with an oil circuit breaker including a relatively fixed cover structure, an oil containing tank, and a plurality of detachable securing means for supporting said tank in depending relation to said cover structure at a plurality of peripheral positions, means for lowering and elevating said tank with respect to said cover structure comprising a pair of single directional acting fluid motors arranged for parallel operation, said motors each comprising relatively movable cylinder, piston and piston rod elements, said cylinder element of each of said motors being provided with a port, means for directly connecting said piston rod elements to said cover structure after removal of and at the same peripheral position as at least two of said detachable supporting means, means for supporting said tank by said cylinder elements when the remaining detachable supporting means are removed from the breaker, means comprising a pneumo-hydraulic accumulator connected to said port of each of said cylinder elements for supplying fluid under pressure, a reservoir connected to said port of each of said cylinder elements, and valve means for draining fluid under pressure from said motors to said reservoir for causing movement of said cylinder elements relative to said piston elements to lower said tank from said cover structure and for sequentially causing fluid under pressure to flow from said accumulator to said motors to cause movement of said cylinder elements relative to saidpiston elements to raise said tank to said cover structure.

9. A device for raising and lowering a tank of an electric device supported above ground or floor level by a frame structure comprising in combination a pair of single directional acting fluid motors arranged for parallel operation, said motors each comprising relatively movable cylinder and piston elements, said cylinder element of each of said motors being provided with a port, means for directly connecting one of said elements of each of said motors to said frame structure, means for supporting the tankof the electric device by another of said elements of each of said motors, a reservoir connected to said port of each of said cylinder elements of said motors, means for forcing fluid from said reservoir to said port of each of said cylinder elements, and valve means for draining fluid under pressure from said cylinder elements to said reservoir for causing relative movement of said elements to lower the tank from the electric device and for sequentially causing fluid under pressure to flow from said source to said cylinder elements to cause relative movement of said elements to raise the tank to the electric device.

References Cited in the file of this patent UNITED STATES PATENTS 2,035,771 Thumin Mar. 31, 1936 2,188,364 Lannen J an. 30, 1940 2,290,320 Dufiing July 21, 1942 2,620,160 Ray' Dec. 2, 1952 FOREIGN PATENTS 465,321 Canada May 23, 1950 1,098,565 France Mar. 5, 1955 

